Muscio, G. P. A. (Corresponding author) ; Institut für Erdöl und Organische Geochemie (Jülich, 4) ; Technische Hochschule (Aachen)

1995
Forschungszentrum Jülich

Report No.: Juel-3094

Abstract: When petroleum is produced from its reservoir at present day, it has already been submitted to a complex array of natural processes, which have left their imprint on its chemical and physical properties. These processes involve the generation of petroleum in its source rock as a function of thermal evolution, and its migration to the reservoir. In order to achieve a better understanding of the effects that these processes have on the nature and occurrence of petroleum, it is crucial to investigate a study area that represents an integrated system encompassing all processes from the beginning of crude oil formation to entrapment. The Bakken Shale petroleum system of the Williston Basin (U.S.A./Canada) appears to fulfil these requirements as it covers a broad range of maturity incorporating an stages of catagenesis, and source and reservoir are closely associated, i.e. Bakken petroleum has not been submitted to long secondary migration routes. Combined with a basinwide uniformity in kerogen type, the latter feature constrains the broad scope of potential influences, and therefore the Bakken petroleum system is an ideal candidate to study petroleum generation, its expulsion and migration under natural conditions. By using a selected set of wens/core samples which were considered to be representative for the entire Bakken petroleum system based on comprehensive screening analyses on both kerogen and bitumen, the present study focussed on the following principal aspects: (I) Evolution of petroleum generation as a function of maturation; (2) Primary migration and distribution of crude oil in a constrained natural system; (3) Occurrence of gas in the immature zone; (4) Evaluation of the natural maturity series with simulation experiments.

Keyword(s): petroleum demand ; petroleum deposit ; petroleum formation ; petroleum geology ; stratigraphy ; organic geochemistry ; organic matter ; bitumen

1. Agrosphäre (ICG-4)